Add 21/70 and 9/42
21/70 + 9/42 is 18/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 70 × 3 = 210,
21/70 = 21 × 3/70 × 3 = 63/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
9/42 = 9 × 5/42 × 5 = 45/210 - Add the two like fractions:
63/210 + 45/210 = 63 + 45/210 = 108/210 - 108/210 simplified gives 18/35
- So, 21/70 + 9/42 = 18/35
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